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SD-33 marine engine, newbie questions

Hello all,
I'm a newbie to diesel engines, just bought a Freeport 41 with an SD-33 in it. the lift pump and feed pump were both disconnected, any notion why? I reconnected the lift pump and it smoothed the idle out. Do these beasts use an air cleaner? If not why? Should the throttle linkage and shutoff linkage have balance or return springs?Thanks for your time

Re: SD-33 marine engine, newbie questions

Hello all,
I'm a newbie to diesel engines, just bought a Freeport 41 with an SD-33 in it. the lift pump and feed pump were both disconnected, any notion why? I reconnected the lift pump and it smoothed the idle out. Do these beasts use an air cleaner? If not why? Should the throttle linkage and shutoff linkage have balance or return springs?Thanks for your time

Rich

It should not need a lift pump as the feed pump on the side of the IP can deliver more than max engine power requires. That's why there is a return line to the tank.
Disconnect the return line with engine running and make sure you are getting a strong flow with no air in it.
If the flow is weak, check the strainer in the banjo fitting of the feed pump inlet.
In the marine setup, a sports air cleaner is all you need.
The original motor had a solenoid shutoff and needed a return spring.
There was a spring attached to the throttle lever on the IP and the bracket below with 5 holes in it. Took a bit of load of the throttle cable.